ADB question

anyone know how i could have adb working when the phone is running normally, but when im in recovery mode adb wont work?

i just applied the latest OTA via an update.zip and only since then i've had this problem... but i cant see how the OTA would be related (since i have root, busybox, sprecovery all back on there. and i have su from both a terminal on the phone and from adb when the phone is on running normally). seems like i just might be forgetting something little... i hope!